What is the meaning of RenderCommand ?

[FishHawk]

I have read the source code for the sprite plugin and I understand what RenderCommand is and how it works.

I just don't know what the meaning is. I need to write 36 lines of code to call the 3 functions of TrackedRenderPass. That looks overly complicated and abstracted. Is this to restrict access to World? Or is this for code reuse?